TRAFFIC LIGHT PRIORITY CONTROL FOR EMERGENCY VEHICLES

P. RAGHUVEER REDDY

(09831A0489)

P. SAI PRANAY RAJ

(09831A0491)

Project Guide :

Ms. SANDHYA PATEL

CONTENTS:

INTRODUCTION

BLOCK DIAGRAM

TRANSMITTER SECTION

POWER SUPPLY

RECIEVER SECTION

INTRODUCTION:

Traffic control has become a major problem on the roads of many cities in India.

Some emergency vehicles like Ambulances, Fire Brigades

and some important Security conveys get stuck in the traffic and have to wait which is not desirable.

The main aim of the project is to provide a wireless control system to these emergency vehicles which controls the traffic

light signals.

BLOCK DIAGRAM:

BLOCK DIAGRAM: The block diagram mainly consists of two sections.

They are :

1.Transmitter Section 2. Receiver Section

Switch Pad RF Receiver Module

HT12E Encoder HT12D Decoder

RF Transmitter Module AT89S52 Microcontroller

LED Indicators

TRANSMITTER SECTION:

The transmitter section mainly consists of

a) Switch Pad b) HT12E Encoder c) RF Transmitter module.

The Switch pad consists of 4 buttons representing the 4 directions at a traffic junction. The switch button type used here is Push button switch. For easy mechanism we can use Selector type switch also.

TRANSMITTER SECTION: The next block is the signal Encoder HT12E. HT represents Holtek Semiconductor Inc and 12E represents the 212 series of Encoders. It converts the parallel information from switch pad into serial for RF transmission. Features:

8 Address pins and 4 Address/Data pins.

Low power consumption.

Highly immune to noise.

Low stand by current (0.1uA) at VDD = 5V. .

Minimum transmission of four words.

TRANSMITTER SECTION The next block is RF Transmitter module TWS - 434. The frequency of the RF signal used in the project is

434 MHz The modulation technique used is ASK Features of the TWS transmitter are:

Operating Frequency : 433.92 MHz

Operating voltage: 1.5-12 V

Output power: 8mW

Operating range: 200 ft

Transfer rate: 3 kbps

POWER SUPPLY:

POWER SUPPLY:Operation:

1. Initially 230 V AC supply is reduced to (0-9V) with the help of a step down transformer having a capacity of 500mA.

2. This low voltage is rectified with the help of bridge rectifier. The ripples are minimized with the help of capacitor filter to get a smooth DC supply. The rating of the chosen capacitor filter is 1000µF

3. The regulated DC voltage is obtained by using a regulator IC 7805

4. Another capacitor filter of rating 10µF is connected at the output of regulator IC to eliminate the voltage oscillations at the output due to the large voltage oscillations at the input of the regulator

RECEIVER SECTION: The RF signal transmitted reaches the receiver section

and controls the traffic lights.

The receiver section works on 5V DC output of the power supply block.

The receiver section has got 4 main components.

They are :

a) RF Receiver Module.

b) HT12D Decoder.

c) AT89S52 uC .

d) LED Indicators.

RECEIVER SECTION: The first block in receiver section is the RF Receiver

RWS-434. It receives the serial data from RF Transmitter through antenna. Features:

Operating frequency: 433.92 MHz

Operating voltage: 3.3V- 9V

Low current consumption

Linear & Digital Outputs

Sensitivity: 3uV

RECEIVER SECTION: The next component HT12D decoder belongs to 212 Decoder series of Holtek Semiconductor Inc. It converts the serial information from RF Receiver into parallel to Microcontroller input. For proper operation , a pair of encoder/decoder with the same number of addresses and data format should be chosen. Features: Operating voltage: 2.4V-12V Low power consumption High noise immunity. Low standby current Received codes are checked 3 times

AT89S52 MC The next component which is main part of the receiver section is the AT89S52 Microcontroller. AT - Atmel , 89 - manufacturer's series , S - Silicon CMOS , 52 - is the family of 8051 i.e., 8052 MC. Features: 8K Bytes of In-System Programmable

(ISP) Flash Memory 256 x 8-bit Internal RAM 32 Programmable I/O Lines Three 16-bit Timer/Counters Eight Interrupt Sources Full Duplex UART Serial Channel Low-power Idle and Power-down Modes Watchdog timer

RECEIVER SECTION:

LED Indicators are used in the project to

represent the traffic light signals. Basic LED consists of:

LED Chip.

Anode & Cathode Frames.

Colored Epoxy lens. The output ports from MC

are connected to these LED’s.

PICTORIAL REPRESENTATION

QUERIES..???

THANK YOU